
\pgfdeclarelayer{back}
\pgfdeclarelayer{fore}
\pgfdeclarelayer{foreback}
\pgfsetlayers{back,foreback,main,fore}
\definecolor{back}{RGB}{21,61,140}
\definecolor{left1}{RGB}{43,60,67}
\definecolor{right1}{RGB}{240,240,215}
\definecolor{bottom}{RGB}{8,77,182}

\definecolor{colorA}{RGB}{214,199,61}
\definecolor{colorB}{RGB}{16,166,194}
\definecolor{colorC}{RGB}{11,127,110}
\definecolor{colorD}{RGB}{23,79,114}

\pdfbookmark[0]{封面}{cover}

\begin{tikzpicture}[remember picture,overlay]
\begin{pgfonlayer}{back}
\fill[back] (current page.south west) rectangle (current page.north east);
\end{pgfonlayer}

\node at (current page.center){
\begin{tikzpicture}
\begin{scope}[yshift=-1cm]
\fill[xshift=-0.1cm,left color=left1,right color=right1,xslant=0.4,yshift=0.4cm](-6,-2)rectangle(6,2);


\begin{pgfonlayer}{fore}
\clip(-4,0)arc(180:360:4 and 0.9)--(4,5)--(-4,5)--cycle;
\fill[ball color=black!60](0,0)circle(4);
\end{pgfonlayer}

\begin{pgfonlayer}{foreback}
\clip(-4,0)arc(180:360:4 and 0.9)--(4,-5)--(-4,-5)--cycle;
\fill[ball color=black!60](0,0)circle(4);
\end{pgfonlayer}
\end{scope}
\end{tikzpicture}
};

\node[white,scale=2] at([yshift=-6cm]current page.north)
{\wryh{史济怀\quad 刘太顺\quad 编著}};

\fill[bottom]([yshift=2cm]current page.south)ellipse(9.5 and 0.7);
\node[white,scale=1.5] at([yshift=2cm]current page.south)
{\ziju{0.5}\wryh{中国科学技术大学出版社}};

\node[scale=7] at([yshift=-3.5cm]current page.north)
{\hyds{\textcolor{colorA}复 \textcolor{colorB}变
\textcolor{colorC}函 \textcolor{colorD}数}};

\end{tikzpicture}
